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Non-contact data access with direction identification for industrial differential serial bus
Kai Xie1, Xiaoping Li, Hanlu Zhang
1School of Electronical and Mechanical Engineering, Xidian University, Xi'an 710071, China. kaixie@mail.xidian.edu.cn
The Review of Scientific Instruments
|July 5, 2013
Summary
This study introduces a safe, non-contact method for accessing industrial serial bus data. The technique reconstructs data streams from electromagnetic fields, enabling effective online testing and diagnostics without conductor contact.
Area of Science:
- Electrical Engineering
- Industrial Automation
- Signal Processing
Background:
- Industrial serial buses like RS-485 are critical for data communication.
- Traditional methods for accessing data require direct conductor contact, posing risks.
- Online testing and diagnostics are essential for maintaining industrial systems.
Purpose of the Study:
- To develop a non-contact method for accessing data in industrial differential serial bus applications.
- To create a safe and effective online testing and diagnosing tool.
- To reconstruct data streams and transmission direction from near-field emanations.
Main Methods:
- A non-contact probe sensing electric and magnetic fields was designed.
- Theories for data reconstruction and direction identification from near-field emanations were developed.
- A prototype circuit was implemented using inexpensive components and tested on an RS-485 bus.
Main Results:
- The proposed method successfully reconstructed data streams and transmission direction.
- Near-field emanations from a twisted pair were utilized for data access.
- Experimental results validated the effectiveness of the non-contact scheme.
Conclusions:
- The non-contact method provides a safe and effective solution for industrial serial bus data access.
- This technique eliminates the need for direct conductor contact, preserving insulation.
- The developed system serves as a valuable tool for online testing and diagnostics in industrial settings.
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